Billed as an offensive juggernaut between the Pac-12's fastest scoring teams, Oregon didn't find its stride until the second half — and Arizona never did — and the Ducks (4-0, 1-0) got their seventh straight conference-opening victory.

Much had been made about the meeting between the quick-striking Ducks under Chip Kelly and Arizona's spread offense under no-huddle, up-tempo pioneer Rich Rodriguez. Oregon went into it the averaging 54 points per game, while Arizona wasn't far behind with an average of a little more than 46 points.

However, Arizona (3-1, 0-1) couldn't find the end zone and quarterback Matt Scott, a fifth-year senior who spent the last two season's behind Nick Foles, passed for 210 yards but was intercepted three times — one returned for a touchdown.

The game got off to a sloppy start as Oregon failed on fourth down and each team turned the ball over before Mariota found Daryle Hawkins with a 17-yard touchdown pass midway through the first quarter.

Arizona got as close as the 2-yard line on the next series, but couldn't punch it in and turned the ball over on downs. The Wildcats' struggles' continued when John Bonano's 31-yard field goal was blocked early in the second quarter.

Rob Beard hit a 27-yard field goal to increase Oregon's advantage to 10-0. It was the Ducks' first FG of the season. Beard added a 41-yarder late in the first half to make it 13-0 at the break.

While both offenses appeared to sputter at times, defenses made the difference in the first half.

Oregon's hybrid 3-4 under longtime defensive coordinator Nick Aliotti held the Wildcats to 141 yards in total offense in the first 30 minutes. Meanwhile, Arizona's new 3-3-5 defense kept the normally prolific Ducks from piling on points.

There was more of the same to open the second half, and the first two possessions by both teams ended in punts.

But then the Ducks started rolling. De'Anthony Thomas returned Arizona's third-straight punt 38 yards, setting up a 35-yard pass to Colt Lyerla, who finished it off with a 1-yard touchdown run. The drive took just three plays and 29 seconds.

Kiko Alonso intercepted Scott, leading to Mariota's long TD pass to Addison, before Ifo Ekpre-Olomu ran his interception back 54 yards to make it 35-0.

Bryan Bennett added an 8-yard scoring run with 4:02 left in the game before Troy Hill intercepted Scott's backup, B.J. Denker, for a 29-yeard touchdown and the final margin.

Arizona opened coach Rodriguez's tenure with a victory over Toledo before upsetting then-No. 18 Oklahoma State 59-38 in their second game. Last weekend in a 56-0 win over South Carolina State, the Wildcats ran a school-record 102 offensive plays.

The Wildcats were the first big test for Oregon, which opened the season with victories over Arkansas State, Fresno State and lower-division Tennessee Tech.

Before this season, Arizona hadn't been ranked in the AP Top 25 since November 2010, when the No. 20 Wildcats were knocked out with a 48-29 loss to the then-No. 1 Ducks.

Last season, Oregon defeated Arizona 56-31 in Tucson.

Oregon's last shutout of Arizona came in 1964, when the Ducks won 21-0 at Hayward Field in Eugene.